(1) Field of the Invention
The present invention relates to an improvement in a decorative silver-colored sintered alloy comprising titanium carbide (TiC) as the main component. More particularly, the present invention relates to a sintered alloy which has a high corrosion resistance and is excellent in the property of manifesting a smooth mirror surface having a deep silver color. Furthermore, the present invention relates to a process for the preparation of this sintered alloy.
(2) Description of the Prior Art
A sintered alloy comprising TiC as the main component and a binder metal selected from Fe, Co, Ni, Mo, W and Ti is broadly used as a decorative material because it has a silver color and is excellent in such properties as the hardness and strength.
However, sintering of TiC per se is very difficult and in order to obtain a sinterd body having a high strength, a binder metal as mentioned above is added as a sintering aid.
Since the above-mentioned sintering aid is a metal element, corrosion of the metal component present in the sintered alloy is advanced and the color of the decorative member is readily degraded by sweat or the like.
Moreover, the sintering aid, especially the metal of the iron group, has no saitsfactory wettability with TiC, and therefore, many voids or pores appear throughout the crystals and grain boundaries in the sintered body, and even if mirror polishing is carried out, a smooth and deep mirror surface cannot be manifested.